Concave mounting



sept. 14, 1937. R BERNHARD 2,093,025'A coNcAvE MOUNTING Fi1edMay 2s, 1955 'Richard eizzafz bAgG/fr A Patented Sept. 14, 1937 UNiTED STATES CONCAVE MOUNTING Richard Bernhard, Allentown, Pa., assignor to Traylor Engineering and Manufacturing Company, a corporation of Delaware Application May 28, 1935, Serial No. 23,937

5 Claims.

This invention relates to gyratory crushers and aims to provide an improved mounting for the concaves of such Crushers.

An important advantage of the invention resides in the provision of means for centering the concave, which is ordinarily of annular one-piece construction, With respect to the axis of gyration of the cone or crusher head, and for resisting the tendency of the concave to rotate Within the top shell in which it is mounted due to the thrust exerted by the cone against the crushing face of the concave.

More particularly, the invention aims to provide a mounting for the concave such that any play that may originally exist between the concave and the top shell is taken up by a slight rotative movement of the concave at the beginning of the crushing operation, further movement tending to tighten or bind the concave within the shell. In the preferred form of my invention this object is accomplished by forming the outer circumference of the concave and the recess in the top shell of such shape that any rotation of the concave causes compression of the interposed filling material between the walls of the concave and top shell, thus locking the concave against further slipping or weaving such as would reduce the effectiveness of the crusher.

Additional objects and advantages of the invention will become apparent from the following detailed description of one preferred embodiment of the invention, reference being had to the annexed sheet of drawings in which:

Figure 1 is a vertical cross-sectional view of the upper portion of a gyratory crusher showing the manner in which the concave is supported within the top shell;

Figure 2 is a transverse cross-sectional view on the line 2-2 of Figure 1, illustrating the polygonal outer circumference of the concave and the polygonal inner circumference of the top shell; and

Figure 3 is a detailed transverse cross-sectional view of the concave and top shell showing the concave slightly rotated With respect to the top shell.

In the gyratory crusher illustrated in Figure 1, the vertical shaft l carries adjacent its top a tapered core 2 covered by a mantle or cone 3 which is held in association with the core by a head nut 4. At its upper end the shaft is suspended by a spider 5 which permits gyratory movement of the shaft. The spider is connected to the inside of a hopper 6 which in turn is supported upon the upper end of a top shell l bolted to and surmounting a bottom shell 8.

Enclosed by the top shell is an annular onepiece concave 9 presenting a crushing face 9a to the cone 3. As will be apparent, ore, rocks or other lump material feedingv from the hopper 6 into the space between the cone 3 and the concave 9 is crushed by the cone against theconcave through the gyratory movement of the cone, and the crushed material passes out the lower end of the concave. For a more detailed descripion of the construction and operation of Crushers of this general class, reference is made to applicants prior Patent No. 1,837,102, granted December 15, 1931.

According to the present invention, the upper end of the bottom shell 8 is provided with arrecess IIl encircling its inner circumference, and the lower end of the concave is provided with a horizontally extending peripheral ange l2 adapted to seat in the recess and accurately position and maintain the concave concentric with the axis of gyration of the cone. The top shell 1 at its lower end is likewise formed with an annular ange I3 seating in a cooperating recess I4 in the upper end of the bottom shell so as to retain the inner circumference of the top shell slightly spaced from Vthe Vouter circumference of the concave.

An important feature of the invention resides in the shape of the concave and top shell. In the present embodiment as best shown in Figure 2, the outer circumference of the concave and the inner circumference of the top shell are made generally polygonal in transverse cross-section with the flats of one circumference disposed substantially parallel to the flats of the other circumference. The small clearance between the concave and top shell is occupied by a relatively soft metal filling I0, such as Zinc. As indicated in the drawing, the maximum radius of the outer circumference of the concave approximates the minimum radius of the inner circumference of the top shell.

At the time of assembly of the crusher, or when an old concave is replaced byl a new one, the molten zinc is poured into the space between the concave and top shell to provide a backing for the concave. However, upon cooling, this zinc filling undergoes a slight contraction with the result that it not infrequently draws away from one of the walls, usually the wall of the top shell, leaving a slight clearance between the filling and adjacent wall. In those cases where the inner circumference of the shell is made cylindrical this shrinkage allows the concave to turn or wabble within the shell during operation of the Crusher which is objectionable for the reason that to operate most efhciently the crushing surface with which the cone 8 cooperates should be stationary.

According to the present invention the concave is constructed so as to be self-tightening. That is to say, when looseness occurs for any 10 reason between the concave and the top shell,

concave against the flats ofthe shell.

up looseness and bind within the top shell.

When it is desired to insert a new concave, all that is necessary is to unbolt the top shell from the bottom shell, apply heat to the outside of the top shell to soften the Zinc lling and then drive the concave from the shell by a few blows of a Sledge hammer. A new concave may be inserted by engaging its flange I2 with the recess I I of the bottom shell, bolting the top shell to the bottom shell, and then pouring molten zinc into the space between the concave and the top shell.

It will be apparent that the concave may be made in sections instead of cast in a single piece. In such cases there might be as many sections u composing the concave as there are ats upon "d its circumference, assuming the concave is of angular or polygonal shape. However the onepiece construction is preferable because of the absence of vertical joints between sections which wear very rapidly and allow the passage of oversize material through the apparatus. So, also,

the shape of the outer circumference of the concave and the inner circumference of the top shell may be other than polygonal so long as the shape is such that relative rotation between the concave and top shell tends to compress the interposed lling material. It will also be obvious that the mounting herein described may be employed in attaching the crushing mantle or cone to the vertical shaft, By the term lling as used in the specication and claims is meant a layer of metal of substantial thickness capable of providing a cushionor backing for one of the grinding elements. Various other changes in structure and design may be made without departing from the spirit of my invention.

I claim:

1. In a gyratory crusher, an annular concave, a top shell surrounding but spaced from the concave, and a lling of yieldable metal between the concave and top shell, the outer circumference of the concave and the inner circumference of the top shell being formed throughout a substantial portion of their areas with corresponding flat faces so as to cause compression of the lling upon rotation of the concave, the maximum radius of the outer circumference of the concave being not substantially less than the minimum radius of the inner circumference of the top shell.

2. In a gyratory Crusher, an annular concave, a top shell surrounding but spaced from the concave, the outer circumference of the concave being polygonal in transverse section and the inner circumference of the top shell being correspondingly polygonal in transverse section, and a metal filling in the space between the outer and inner circumferences, the maximum radius of the outer circumference of the concave being not substantially less than the minimum radius of the inner circumference of the top shell.

3. In a gyratory Crusher, an annular concave, a top shell surrounding but spaced from the concave, the outer circumference of the concave being polygonal in transverse section and the inner circumference of the top shell being correspondingly polygonal in transverse section, a relatively soft metal filling in the space between the outer and inner circumferences, a bottom shell supporting the top shell and concave, and an intertting tongue-and-slot connection between the concave and the bottom shell, the maximum radius of the outer circumference of the concave being not substantially less than the minimum radius of the inner circumference of the top shell.

4. In a gyratory crusher, an annular crushing element, an annular supporting element located in concentric spaced relation to said crushing element and a filling of soft metal between the crushing element and supporting element, the outer circumference of one of said elements and the opposed inner circumference of the other of said elements being in transverse cross-section of geometrically similar non-circular outline and being so` constructed and arranged that rotative movement of one of the elements relative to the other tends to compress rather than shear the filling between two opposed faces throughout substantial Aportions of the circumferences of the elements.

5. In a gyratory Crusher, an annular crushing element, an annular supporting element located in concentric spaced relation to said crushing element and a filling of soft metal between the crushing element and supporting element, the outer circumference of one of said elements and the opposed inner circumference of the other of said elements being in transverse cross-section of geometrically similar non-circular outline throughout their major areas and the maximum radius of said outer circumference being not substantia'lly less than the minimum radius of said inner circumference.

RICHARD BERNHARD. 

